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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Effect of vitamin B6 depletion in adult man on the metabolism of methionine, on the plasma concentration and the urinary excretion of amino acids and on the excretion of viamin B6 and 4-pyridoxic acid

Park, Youngmee K. January 1970 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.
42

The effect of a vitamin B12 deficiency on folic acid metabolism in germ-free and conventional rats

La Iacona, Barbara Gail, January 1968 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1968. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
43

Untersuchungen zu den Blutserumkonzentrationen an Vitaminen aus dem B-Komplex bei Milchkühen

Klein, Bärbel. January 1900 (has links)
Freie Universiẗat, Diss., 2004--Berlin. / Dateiformat: zip, Dateien im PDF-Format. Erscheinungsjahr an der Haupttitelstelle: 2004.
44

Hematologic and Vitamin Status of African American Women and Their Relationships to Pregnancy Outcome

Knight, Enid M., Spurlock, Bernice G., Johnson, Allan A., Oyemade, U. Jean, Cole, O. Jackson, West, William L., Manning, Malcolm G., Nolan, George, Bonds, Duane, Laryea, Haziel, Jones, Sidney, Westhey, Lennox, Edwards, Cecile H. 01 January 1991 (has links)
A prospective observational study was conducted to investigate the effects of nutrition and related factors on the outcome of pregnancy in nulliparous African American women 16-35 years of age. Blood samples from a subset of these subjects were taken during the first (1st), second (2nd) and third (3rd) trimesters of pregnancy and at delivery. Cord blood samples were also collected at delivery. Levels of selected biochemical variables including serum ferritin, vitamin B12 and folate as well as whole blood folate, and selected hematologic indices were determined and correlated with pregnancy outcome variables. During the second trimester of pregnancy, values for hematocrit and hemoglobin were less than 30% and 11 g/dL, respectively, in 16% and 30% of the participants, respectively. Serum and whole blood (WB) folate increased sequentially during pregnancy. Cord concentrations of serum folate were significantly higher than maternal concentrations at delivery (P<0.05). Serum ferritin declined significantly from 36±5.6 ng/ml in the first trimester to 17±1.5 ng/ml during the 3rd trimester (P<0.05), and returned to the 2nd trimester level (26±2.0 ng/ml) at delivery. Second trimester WB folate was positively related to birth weight (R2=0.21), while gestational age was inversely correlated with 3rd trimester vitamin B12 (R2=0.34). These data suggest that vitamin B12 and folate play an important role in the outcome of pregnancy in this population.
45

Fate of B-complex vitamins in the gastrointestinal tract of dairy cows

Santschi, Debora January 2004 (has links)
No description available.
46

Biosynthesis of Vitamin B₆

Hill, Robert Edward 05 1900 (has links)
The biosynthesis of vitamin B₆ was studied by administering radioactive putative precursors to a mutant of Escherichia coli B., WG2. A new method for the isolation and purification of the vitamin congener, pyridoxol, is described. Partial degradation of the radioactive pyridoxol revealed non-random incorporation of a number of precursors into pyridoxol. On the basis of these results a biosynthetic scheme was constructed which envisages that pyridoxol is derived from three glycerol units. One of these is incorporated via pyruvic acid as a two carbon fragment at the oxidation level of acetaldehyde. The other two are incorporated intact, possibly by way of triose phosphate (Fig. 33). / Thesis / Doctor of Philosophy (PhD)
47

Identification and quantitation of urinary methylmalonic acid by gas chromatography - Mass fragmentography.

January 1996 (has links)
by Lai Wai Kai. / Thesis (M.Sc.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 70-74). / Acknowledgement --- p.iv / Abstract --- p.v / Figures and Tables --- p.vii / Abbreviations used in this study --- p.ix / Contents / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Biochemistry of cobalamin --- p.2 / Chapter 1.1.1 --- Biological functions of cobalamin --- p.2 / Chapter 1.1.2 --- Causes of cobalamin deficiency --- p.4 / Chapter 1.1.3 --- Significances of cobalamin deficiency --- p.7 / Chapter 1.1.4 --- Assessment of cobalamin deficiency --- p.8 / Chapter 1.2 --- Biochemistry of Methylmalonic acid (MMA) --- p.10 / Chapter 1.2.1 --- Elevation of MMA in biological fluids --- p.11 / Chapter 1.2.2 --- Significances of measurement of MMA --- p.11 / Chapter 1.2.3 --- Methods of measurement of urinary MMA --- p.13 / Chapter 2. --- Objectives of this project --- p.16 / Chapter 3. --- Materials and Methods / Chapter 3.1 --- Study subjects --- p.18 / Chapter 3.2 --- Sample collection --- p.18 / Chapter 3.3 --- Biochemical and haematological analysis --- p.18 / Chapter 3.4 --- Measurement of urinary creatinine concentration --- p.19 / Chapter 3.5 --- Measurement of serum cobalamin concentration --- p.20. / Chapter 3.6 --- GC-MS determination of urinary MMA --- p.21 / Chapter 3.7 --- Statistical analysis --- p.24 / Chapter 4. --- Results / Chapter 4.1 --- Clinical features of subjects --- p.28 / Chapter 4.2 --- General blood analysis --- p.28 / Chapter 4.3 --- Serum cobalamin analysis --- p.30 / Chapter 4.4 --- Urinary MMA analysis --- p.33 / Chapter 4.5 --- Relationship between urinary MMA excretion and age --- p.53 / Chapter 4.6 --- Relationship between urinary MMA excretion and serum cobalamin concentrations --- p.53 / Chapter 5. --- Discussions / Chapter 5.1 --- Serum cobalamin analysis --- p.62 / Chapter 5.2 --- Urinary MMA analysis --- p.62 / Chapter 5.3 --- Relationship between urinary MMA excretion and age --- p.66 / Chapter 5.4 --- Relationship between urinary MMA excretion and serum cobalamin concentration --- p.66 / Chapter 5.5 --- Relationship between urinary MMA excretion and diet --- p.68 / Chapter 6. --- Conclusions --- p.69 / Chapter 7. --- References --- p.70
48

The Response of Elderly People to a B-6 Supplement

Chaomuangbon, Sunthorn 08 1900 (has links)
Vitamin B-6 status was examined in a group of 46 elderly subjects who were selected from nursing home residents, hospital patients, and free living individuals in Denton County. Subjects were limited to men and women over 60 years of age. Erythrocyte aspartate aminotransferase stimulation with pyridoxal phosphate (in-vitro) was studied as the biochemical criterion of vitamin B-6 status. The pyridoxine status of these 46 subjects (the reference group) was measured in order to be able to identify people with a relatively poor B-6 status. A sub-group of the reference group was composed of 4 subjects who took B-6 supplements (supplemented group). There was no significant difference (0.05 level) in the basal activity, stimulated activity, percentage stimulation, or body weight, after treatment with 10 mg pyridoxine hydrochloride for 4 weeks, even though all 4 subjects had an improved B-6 status (based on percentage stimulation) after taking the supplement. The data indicated that of the 4 subjects tested, 2 showed a large change in the basal activity, stimulated activity, and percentage stimulation. The lack of significant difference (0.05 level) was probably due to a small sample size. One subject reported an increased appetite and body weight after treatment with pyridoxine.
49

THE ROLE OF A AND B VITAMINS DURING OROFACIAL DEVELOPMENT OF XENOPUS LAEVIS

Kennedy, Allyson 21 June 2012 (has links)
Orofacial anomalies make up about a third of the 120,000 birth defects each year in the United States. Children born with these abnormalities must undergo immense physical and emotional strain in order to correct the defects. In fact, about $697 million is spent every year surgically treating children with cleft lip and/or cleft palate (2011). In countries where surgery is not an option, this abnormality causes immense difficulties in eating, hearing, speech, and psychosocial development. The causes of cleft lip/palate are extremely complex. Genetics play a role in the anomaly; however, 95% of cleft palate cases are non-syndromic and likely due to other factors. Vitamin deficiencies, lack of folic acid intake during pregnancy, exposure to cigarette smoke, anticonvulsant drugs, alcohol, and inappropriate amounts of retinoic acid have all been correlated to incidence of cleft palate and other orofacial defects (Weingartner, Lotz et al. 2007). Xenopus laevis, and the closely related Xenopus tropicalis, are excellent model systems for orofacial development studies. The ease of embryo collection and manipulation, in addition to the conservation of DNA sequence between the two species, makes them ideal for studying developmental processes. Further, tissue specific experiments are extremely feasible due to the size of Xenopus oocytes (approximately 1000 times larger than a human egg!), and their ability to develop outside of the mother (Lindeman, Winata et al. 2010; Liu 2011). Here, I show that molecules from both the folic acid and retinoic acid pathways are highly expressed in the developing face. I have found that inhibition of key enzymes that regulate these pathways induces similar orofacial malformations, including median clefts that extend into the developing palate. Further, disruption of these pathways induces severe abnormalities in the formation of the cartilages of the jaws and face. Thus, both folic acid and retinoic acid are key signaling molecules that regulate proper formation of the orofacial region.
50

Prevalence and Possible Causes of Vitamin B-6 Deficiency Among Women in the Philippines

Wong, Siew Sun 01 May 1999 (has links)
Recently maternal intake of multivitamins has been associated with a reduced risk of orofacial clefts (OFC)in human epidemiologic studies. In the Philippines, vitamin B-6 deficiency was found to be associated with increased risk of OFCs. The birth prevalence of OFCs in the Philippines is among the highest known, but Filipino emigrants in the United States have lower rates, indicating that environmental factors may play an important role in causing OFCs in the Philippines. The prevalence and possible causes of vitamin B-6 deficiency were investigated through dietary and biochemical assessments in case-control study in Negros Occidental, Philippines. Mothers with OFC offspring (cases) were ascertained during a 2-week OFC surgical mission of Operation Smile in 1997, and mothers without OFC offspring (controls) were recruited at randomly selected neighborhood health centers. Sixty-three percent case-mothers and 41 percent control-mothers were vitamin B-6-deficient. Dietary vitamin B-6 intake was low in both cases and controls but lower in cases. Case-mothers consumed 9.4 percent fewer calories than the control-mothers. Rice was the major contribution of total energy, carbohydrate, and protein for both cases and controls. Both cases and controls consumed fruits, seafood, dairy, fats, and oils with similar frequency, but cases consumed grains and grain products, vegetables, meats, beans and bean products, and roots less frequently. The vitamin B-6 activity coefficient, an indicator of vitamin B-6 deficiency, was correlated positively with plasma homocystine and negatively with plasma and red cell folate in cases only. No significant correlations were found between vitamin B-6 status and maternal age, smoking, or drinking, in either cases or controls. Vitamin B-6 deficiency appears to be an important yet complex problem in Negros Occidental because it is widespread and strongly associated with the risk of OFC birth defects. This condition may be a consequence of 1) high polished rice consumption, 2) low vitamin B-6 intake from other food sources, 3) presence of glycosylated vitamin B-6 in plant foods, 4) high vitamin C-induced vitamin B-6 hydroxylation, or 5) a potential zinc deficiency.

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